title: Long-observation-window band-selective homonuclear decoupling: increased sensitivity and resolution in solid-state NMR spectroscopy of proteins.
abstract: Sensitivity and resolution are the two fundamental obstacles to extending solid-state nuclear magnetic resonance to even larger protein systems. Here, a novel long-observation-window band-selective homonuclear decoupling (LOW BASHD) scheme is introduced that increases resolution up to a factor of 3 and sensitivity up to 1.8 by decoupling backbone alpha-carbon (C(α)) and carbonyl (C') nuclei in U-(13)C-labeled proteins during direct (13)C acquisition. This approach introduces short (<200 μs) pulse breaks into much longer (~8 ms) sampling windows to efficiently refocus the J-coupling interaction during detection while avoiding the deleterious effects on sensitivity inherent in rapid stroboscopic band-selective homonuclear decoupling techniques. A significant advantage of LOW-BASHD detection is that it can be directly incorporated into existing correlation methods, as illustrated here for 2D CACO, NCO, and NCA correlation spectroscopy applied to the β1 immunoglobulin binding domain of protein G and 3D CBCACO correlation spectroscopy applied to the α-subunit of tryptophan synthase.
authors.affiliation: Bruker BioSpin Corporation, Billerica, MA 01821, United States.
authors.forename: Jochem O
authors.initials: JO
authors.lastname: Struppe
authors.forename: Chen
authors.initials: C
authors.lastname: Yang
authors.forename: Yachong
authors.initials: Y
authors.lastname: Wang
authors.forename: Roy V
authors.initials: RV
authors.lastname: Hernandez
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Shamansky
authors.forename: Leonard J
authors.initials: LJ
authors.lastname: Mueller
mesh_terms: D002247:Carbon Isotopes; D019204:GTP-Binding Proteins / Q000737:chemistry; D005998:Glycine / Q000737:chemistry; D007074:Immunoglobulin G / Q000737:chemistry; D007553:Isotope Labeling; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011506:Proteins / Q000737:chemistry*; D012486:Salmonella typhimurium / Q000737:chemistry / Q000201:enzymology; D059629:Signal-To-Noise Ratio; D014367:Tryptophan Synthase / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D007074:Immunoglobulin G; D011506:Proteins; D019204:GTP-Binding Proteins; D014367:Tryptophan Synthase; D005998:Glycine
keywords: Band-selective homonuclear decoupling; Correlation spectroscopy; Increased resolution; Increased sensitivity; Protein solid-state NMR